This NIEHS training grant has been active for 30 years and has supported 102 pre-doctorates and 15 post-doctorates. These trainees have gone on to successful careers in toxicology in academia, industry, government and the private sector. This training program has been extensively revised to be in accord with the NIEHS mission and the new NIEHS T32 guidelines. The objective of this training program entitled, Molecular Pathways to Pathogenesis in Toxicology, is to provide trainees with the skills and knowledge necessary to investigate and elucidate how environmental toxicants/cellular stressors contribute to toxicity and influence disease outcomes. The broad overarching research theme is to understand how toxicants/stressors perturb cellular signaling pathways and deregulates gene expression, and how this peturbation/deregulation contributes to toxicity and disease outcomes. Specific environmental-associated human diseases/conditions such as asthma, lung fibrosis, reproductive/endocrine abnormalities, developmental abnormalities and cancer as well as ROS- related toxicity will be the focal molecular/cellular research areas. Examples of types of environmental agents that will be investigated include environmental carcinogens, pesticides, particulates, metals, endocrine disrupters and nanoparticles. There are eighteen faculty from 3 colleges and 6 departments that are participating in this interdisciplinary training program. Importantly, this training grant is administered through the Department of Environmental and Molecular Toxicology which provides a structured cohesive environment for trainees. Pre-doctoral trainees acquire a solid background by completing coursework in toxicology, molecular biology, pharmacology, statistics, and pathology. Pre/postdoctoral trainees receive training in ethics, grant writing and oral communication skills. Pre/postdoctoral trainees participate in a weekly seminar program both as members of the audience and as presenters. Each semester a former trainee is invited back to the Department to present a seminar and to share their career experiences with current trainees. A plan is in place with the College of Veterinary Medicine that will enhance the recruitment of veterinarians (DVMs) interested in human health to postdoctoral positions on this grant. Support for 6 pre-doctoral and 3 postdoctoral trainee positions is requested. Relevance: The proposed research training involving toxicants, signaling pathways/cascades, toxicity and disease will aid society to: 1) assess the impact of environmental factors on human health and disease, 2) understand the mechanisms through which toxicants produce their adverse effects, 3) identify potential human health hazards and prevent diseases and unnecessary exposure to toxic agents.